5. Worried about St. John's wort
Lawrence Berkeley National Laboratory.
Hidden injections given through IV lines are less
effective than "open" (obvious) injections.
For
many years, the placebo effect was a researcher's nightmare. Just because
people took part in research, they get better. Not all of them, but enough
to bollix up the statistics.
A similar phenomenon occurs in the doctor's office, researchers believe. "The placebo effect is a context effect," explains Fabrizio Benedetti, a neuroscientist at the University of Turin, who investigates how the placebo effect influences pain. "Words, touch, smell, sight are the context of medicine."
Context determines expectations, and expectations are the root of the placebo effect.
Now, after years of trying to sidestep placebo, researchers have figured something out: If mindset and expectation can influence health, isn't that something we should know about?
Because
the placebo effect could explain why such alternative approaches as energy
healing or prayer can work -- without a doctor touching a patient or giving
a single drug -- the research is part of the new interest in studying
complementary and alternative medicine.
Said it ain't so...
The placebo effect has never been popular among medical
doctors, who have made it less welcome than a hungry pack of coyotes at
a shepherd's convention. Skeptics got a new argument in May 2001, when
Danish researchers published -- and the media trumpeted -- a debunking
of the effect in the New England Journal of Medicine. After looking at
114 previous studies, Peter Gotzsche and Asbjorn Hrobjartsson concluded
that, aside from pain, the placebo effect was -- nothing.
Nadasville.
In covering the study, the New York Times scoffed that placebo was "more myth than science."
Painkillers
work much better when patients know they are getting them. Data
for Metamizal from "Response Variability ..." in the bibliography).
But critics noted that Linde had lumped research on several ailments, perhaps masking the effectiveness of particular placebo treatments on particular diseases. At any rate, one study failed to derail the growing interest in how the mind can heal the body.
As evidence for the placebo effect continues to mount, it increasingly takes the form of hard data. To the average physician, PET and MRI scans maybe tougher to ignore than patient testimony.
Placebo pain (studies)
In pain research, Benedetti and colleagues have compared
hidden and open administration of painkillers in 278 post-operative patients
in two conditions:
Open vs. hidden administration: To study placebo's psychological roots, patients got the painkiller either via injection ("open") or an existing intravenous line ("hidden")
The results (see "Response Variability ..." in the bibliography) were clear: Open administration makes painkiller work better. The difference, Benedetti says, is the placebo effect. And because opiate antagonists reduce the placebo effect, it seems that the placebo effect occurs when the brain -- expecting pain relief -- causes the body to produce endogenous opioids -- natural painkillers.
Translated, if you expect to get painkillers, your body may produce them for you. Still, no matter how great the placebo effect may be, it relies on deception. That may be legitimate for research studies, but not in the real world.
Says Straus: "You can't deceive the patient in clinical medicine." So before anybody puts this valuable thing into practice, there are ethical hurdles to jump.
Still, you can hypnotize patients...
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